Heating apparatus and fuel flow controlling means therefor



Jan. 10, 1950 w. s. LANDON 2,494,394

HEATING APPARATUS AND FUEL ELow coNTRoLLrNG MEANS THEREFoR Filed oct.11, 194s Fla-I 2 5f 25E' INVENTOR 45 25 www'. ,J

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.ALL ATTORNEY Patented Jan. l0, 1950 HEATING APPARATUS AND FUEL FLOWCONTROLLING MEANS THEREFOB Walter S. Landon, Detroit, Mich., assignor toDetroit Lubricator Company, Detroit, Mich., a corporation of MichiganApplication october 11, 1943, sci-m No. 505,744

7 Claims. (Cl. 158-36) My invention relates to new and usefulimprovements in heating apparatus and more particularly to means forcontrolling the supply of liquid fuel to a heating apparatus having amain burner and a pilot burner.

An object of the invention is to provide means to increase the ow offuel to the pilot burner upon supply of fuel to the main burner.

Another object is to provide means to determine the maximum supply offuel to the pilot burner.

Another object is to provide means to regulate the flow of fuel to thepilot burner and tothe main burner.

Another object is to provide means to determine the maximum flow of fuelto the pilot burner by the regulating means at which fuel will beinitially supplied to the main burner.

Another object is to provide cleaning means for the means for supplyingfuel to the pilot burner.

Another object is to provide safety means for stopping the supply offuel upon failure of combustion in either the main burner or the pilotburner.

The invention consists in the arrangement and cooperative relation ofparts and in the heating apparatus control effected or accomplished bysuch parts, all to be more fully described hereinafter and the noveltyof which will be particularly pointed out and distinctly claimed.

In the accompanying drawings to be taken as a part of this specificationthere are fully and clearly illustrated several preferred embodiments ofthe invention, in which drawings:

Figure 1 is a view of part of a heating apparatus in .vertical centralsection and having operatively connected thereto one control means ofthis invention and shown partly in vertical section and partly inelevation;

Fig. 1 is a detail view of the overcenter lever trip mechanism shown inFig. 1,

Fig. 2 is an enlarged detail view in section on the line 2-2 of Fig. 1;

Fig. 2 is a detail plan view of the adjustment knob and high-nre andpilot iire stops shown in Fig. 2,

Fig. 3 is an enlarged detail view in section that in Fig. 1 and havingoperatively connected thereto another form of control means.

Referring to the drawings by characters of reference, I designatesgenerally the main liquid fuel burner, preferably of the pot type, of aheating apparatus having a liquid fuel pilot burner 2, also preferablyof the pot type. The main burner I has a bottom wall 3 with a. centralopening or aperture l therethrough which is surrounded by an oilretaining ring or wall 5 cooperable with the cylindrical burner sidewall 8 to provide an annular fuel receiving space or pan 1. The sidewall 6 is provided with a plurality of rows of combustion air supplyports 8. The top wall of the burner I has a burner opening 9. 'I'hepilot burner 2 is positioned beneath the opening 4 in registry therewithand preferably has the upper edge of its side wall I0 engaging the underside of the main burner bottom wall 3 so that the flame from the pilotburner 2 will discharge upwardly through the opening 4 into the mainburner I for igniting the fuel in the pan 1. The side wall I0 has aplurality of rows of combustion air supply ports I I. The pilot burnerbottom wall I2 cooperates with the side wall Il! to provide an oilreceiving pan or space I3.l

Opening through and secured in an aperture in the main burner side wall6 adjacent the bottom wall 3, there is a fuel supply pipe or conduit I4which extends laterally and preferably horizontally to an upright,preferably vertical, main fuel supply conduit or pipe, generallydesignated I5. The conduit I 4 is connected into the conduit I5 by meansof the side opening of a T-iltting I6 having its alined openingsvertically positioned and connected respectively to an upper pipe Il anda lower pipe I8. The lower end of the pipe I8 is connected into theyside opening of a T-iitting I9 which has one of its alined end openingsconnected to a laterally extending, substantially horizontal pilotburner fuel supply p ipe or conduit 20 which has its free end openingthrough and secured in an aperture in the pilotburner side wall IIIadjacent the bottom wall I2 for supply of fuel to the space I3. Theother alined end opening of the fitting I9 .is provided with a reductionbushing 2| such that thebottom surface of the bushing bore or port isabove the level of the bottom surface of the conduit 20 in order toprovide a dam or partition 22 to normally direct the flow from the mainconduit .I5 into the branch conduit 20. The height of the dam 22 alsodetermines the fuel level in the pilot burner space I3 and in the branchconduit 20, say at the level indicated by line A, at which fuel will owover the dam and through the bushing 2li. In the pipe I8 adacent itsupper end there is an annular internal restriction or shoulder 23Providing a calibrated oriiice 24 positioned a predetermined distancebelow the horizontal bottom surface of the fitting lateral port 25 andof the branch conduit i4 indicated by the line B such that the liquidhead on orifice 24 will be limited by the outflow through port 25 anddetermine the maximum rate of fuel iiow through the orifice 24.

The conduit I is fed or supplied above the level of the orifice 24 withliquid fuel from a fuel supply means or device generally designated 26capable of variably controlling the supply of fuel at constant rates.The device 26 has a constant level liquid chamber 21 in which the liquidlevel is maintained substantially constant by an inlet needle valve 28operated by a float and level' mechanism 29 in a manner well known inthe art. The chamber 21 is supplied with liquid fuel from any suitablesource of supply such as a tank, not shown, through a pipe 30 connectedinto a strainer chamber 3l' from which the fuel ows to the chamber inletport 32 controlled by the valve 28. Outow of liquid fuel from' thechamber 21 is through an aperture 33B and outlet port 35 to the conduitI5 and is controlled by a meterlng valve 33 having a V-slot 34controlling iiow through the outlet port 35 positioned below the chamberliquid level, indicated by the line L-L of Fig. 2. The stem 36 of valve33 has a left hand screw thread 38 of steep pitch adjustablyscrewthreaded in the sleeve 39 for vertically adjusting the valve 33 tocontrol the rate of now through outlet 35. The stem 36 is provided withahand grip and stop member or knob 40 engageable with a low or pilotfire stop member 4I and with a high fire stop member 42 for limitingrotary motion thereof. The outlet 315 opens into an inclined passagewayconnected at its upper end into a vertical hollow boss 43 which has itslower end screw-threadedly connected to the upper end of the pipe I 1.At the upper end of the boss 43 and alined with the orifice 24 there isa rotatable plug or supporting member 44 having a screw driver slot inits upper outer end for rotation of the plug. Secured to the lower innerend of the plug 44 and extending downward through the boss 43 and thepipe I1 and through the orifice 24 there is an orifice cleaning memberor wire 45 which is bent or offset or excentrically mounted so that itwill scrape -the side wall of the orice 24 upon rotation of the plug 44.The Wire 45 is preferably of polygonal cross section, say triangular asin Fig. 3, for at least that portion of its length which extends throughthe orifice 24. It may be noted that the wire 45 should at all timeshave contact with the side wall of orifice 24 so that it will not createa change in flow rate, as would be the case if it had its position,radially of the orifice 24, altered upon rotation of the plug 44.

Safety means are provided for closinggtherinlet valve 23 to shut offiiow to the mainc'duit I5 and the heating apparatus in the event ofpredetermined excess liquid level in the chamber 21 or upon rise ofliquid level in the fitting I9 above the line A. The chamber 21 has anoverflow outlet 48 which determines the maximum level permissible inchamber 21. The outlet 46 discharges into a cup 41 carried by anddischarging through its bottom wall into a vertical conduit or pipe 48which, at its lower end, is connected into one of 75 and 'pass throughthe pipe 50 and the outlet 5I intol lil the alined end ports of aT-iitting 49. The lateral port of fitting 49 is connected by a pipe orconduit 50 to the bore of bushing 2i so that oil iiowing into thefitting through pipe 48 or pipe 50 will be discharged downward throughthe other alined or bottom fitting outlet 5I. Positioned below theoutlet 5I there is a bucket or container 52 which is connected by avertical link or supporting member 53 to one end of a safety lever 54plvotally supported as at by the control device 26. The lever 54overlies the inlet valve 2S and is engageable therewith to positivelyseat the same and close the inlet 32. The lever 54 and empty container52 are supported in inactive upper position by an overcenter spring 56.When liquid which overflows through the outlet 5I fills the bucket 52 toa predetermined value the increased Weight on the lever 54 will causethe same to pivot about pin 55 sufficiently to move the spring 56 fromits overcenter position to a position overcenter in the oppositedirection. In so moving, the lever 54 will engage the upper end of thevalve stem 28 and the combined force of the trip bucket mechanism. theliquid therein, and the spring 56 will cause the lever 54 to positivelymove the valve stem 28 to closed position.

outlet 35 will be at the rate of say 2 ccs. per minute. which flow willbe passed by the orifice 24 so that there will be no iiow through branchconduit I4. With the stem stop member 40 against the pilot stop member 4I the fuel fiowing into the pilot burner space I3 is ignited by anysuitable means and the heating apparatus will continue to operate at alow pilot lire. If it is desired to start the main burner I, then thestem 36 is rotated counter-clockwise away from the stop member 4I tosome position, such as is shown in Fig. 1, which will open the meteringvalve 33 to provide a iiow through the outlet 35 at a rate greater than4 ccs. per minute. This increased flow will result in an increasing rateof ilow through the orifice 24 as the liquid head on the orifice buildsup to the line B, thereby causing an increasing rate of combustion inthe pilot burner 2. When the head on orifice 24 reaches the line B theexcess oil will flow through the outlet 25 and branch conduit I4 intothe main burner space 1 for ignition by the increased pilot flame. Thediameter of port 25 and conduit I4 is suilicient so that there will besubstantially no increase of liquid level above the line B when thevalve 33 is moved to full open position with the stop 4I) against thestop member 42 and therefore the rate of flow through the oririce 24 andthe size of the ilame in the pilot burner 2 will be substantiallyunchanged for all adjustments of the valve 33 at which fuel will be fedto the main burner I. In order to assure .that a constant flow rate willbe maintained to the pilot burner 2 for any setting of the valve 33, thecleaning member supporting plug 44 will occasionally be rotated so as toclear the orifice 24 of any accumulated wax or other foreign matter, thesharp edge of the wire 45 serving to scrape the side wall of the orice.If, for any reason, fuel collects in.

anche the container 52, the dam 22 limiting the height to which theliquid can collect in the space I3. When the Weight of the liquid incontainer 52 is sufficient to overcome the component of force of spring5B, then the rod 53 will be pulled downward, thereby rotating the lever54 on its fulcrum or pivot 55 to move the spring 58 overcenter,whereupon the lever 54 will be moved sharply downward into engagementwith the valve 29 and close off further inflow of fuel to the chamber21. This closure of valve 28 will stop further flow of fuel to the pilotburner 2 as soon as the liquid level in chamber 21 drops below the inletto the outlet port 35. If the fuel supplied to the main burner I is notignited for any reason, then, when the level of theliquid in the space 1increases sufliciently to overflow the wall or ring 5, the overflowingfuel will discharge into the pilot burner space I3 and flow thencethrough the branch conduit 20 and the pipe 59 and outlet 5| into thecontainer 52 to close off the valve 28 as above described and stopsupply of fuel to the burners I and 2. In addition, if the floatmechanism 29 should fail to function or if, for any other reason, thelevel in chamber 21 should increase above the overow outlet 46, then theexcess liquid will be discharged into the container 52 and operate thesafety trip mechanism to close valve 28 in the same manner as for fuelflow through pipe 59. thereby stopping the supply of fuel to the burnersand 2. It will be apparent that the safety trip mechanism can be readilyreset by swinging the supporting member 53 outward and tipping thecontainer 52 to drain it of liquid fuel, whereupon the member 53 wouldbe pushed upward to return the spring 5E to its overcenter position asshown in Fig. 1, and the container 52 repositioned beneath the outlet5|.

Referring to Fig. 4, the control device differs from that of Fig. 1 onlyin the following respects. The boss 43 has its lower end changed so asto position its connection to the pipe I1 of conduit 5 in verticalalignment with the metering valve outlet 35, the upwardly inclinedpassageway, here designated 68, being retained to vent air to atmospherewhich might collect in the pipe or conduits on the outlet side oforifice 35. The cleaning member 45 of Fig. l, here designated 5I, issecured directly to the bottom end of the metering valve 33 in anysuitable manner so that the orifice 24, here designated 62, will becleaned and have its side wall scraped to remove wax and other foreignmatter on each operation of the metering valve. If it is desired toclean the orifice 62 at additional times. the

same may be done by a quick operation and return of the metering valve33 to its desired setting. The orifice 62 is here shown as carried byand formed through an adjustable sleeve or plug 63, preferablyadjustably screw threaded in the bore of the pipe I8, so that theposition of the orifice relative to the bottom surface of the port 25and branch conduit I4 can be adjusted to regulate the maximum liquidhead onthe orice 62 and accordingly the maximum rate of flow of liquidfuel to the pilot burner 2. From the foregoing description of this Fig.4, it is believed that the operation of the control device and theheating apparatus, when changed as shown in Fig. 4, will be apparentwhen taken in connection with the description of Fig; l. and no furtherdescription is deemed necessary.

Referring to Fig. 5, the heating apparatw:` has a main liquid fuelburner 10 of the pot type having a bottom wall 1I cooperable with acylindri- 6 cal side wall 12 to provide a mixing chamber 18 and an oilreceiving space or pan 14. Through ,the side wall 12 there are aplurality of rows of air inlet holes or ports 15 for supplying primarycombustion air to the chamber 13. The burner 18 may be provided with asurrounding jacket 16 which provides an annular compressed air supplychamber 11, which may be supplied with air undery pressure by anysuitable means such as a blower 81* or the like discharging into thechamber 11 through the inlet duct 18. Liquid fuel is supplied to theburner space 14 through a laterally extending and substantiallyhorizontal conduit or pipe 19 which opens through and is secured in thewall 12 adjacent the bottom wall 1|, the conduit 19 preferably beinginclined slightly downward toward the wall 1|. Extending upward into thechamber 13 there is a liquid fuel pilot burnery preferably of the pottype having a bottom wall 8| and a cylindrical side wall 82 cooperabletherewith to provide a mixing chamber 83 and a liquid fuel receivingspace or pan 84. The side Wall 82 is connected or joined directly to themain Vburner bottom wall 1| so that the bottom Wall 1| will be heated byconduction from the pilot burner 80. The chamber 83 is surrounded by ajacket 84 which provides an annular compressed air chamber 85 forsupplying primary air to the chamber 83 through a plurality of rows ofprimary air inlet ports or openings 86. The chamber 85 is supplied withair under pressure through a duct 81 which may be supplied with airunder pressure from a blower 81a or the like, but which preferablyextends into the chamber 11 and has its open end portion or inlet 88positioned above the level of the lowermost row of air inlet ports 15.The air supply to the duct 81 from the chamber 11 is controlled in anysuitable manner as by a valve or damper 89 positioned in the duct 81 andwhich may be thermostatically or otherwise controlled in accordance withan increase in the fuel supply to the pilot burner. The bottom wall 1|is provided with a plurality of ports or apertures 90 so that the airsupplied by the duct 81 can pass into the upper part of the chamber 85for ow through the air supply ports 86. Liquid fuel is supplied to thepilot burner space or pan 84 through a lateral substantially horizontalconduit or pipe 9| which opens through and is secured in the side wall82 adjacent the bottom wall 8|. The main burner fuel conduit 19 ispositioned above the pilot burner fuel supply conduit 9| and theseconduits extend from and are supplied with liquid fuel by an uprightsubstantially vertical main fuel supply conduit 92. Positioned in theconduit 92 intermediate the levels of the conduits 19 and 9|, there isan annular flange or sleeve which may be adjustable as in Fig. 4 andthrough which'there is a calibrated fuel ow controlling orifice 93. Theoriilce 93 is positioned a predetermined distance below the level of thebottom edge of the opening 94 which leads from the main conduit 92vintothe main burner conduit 19. The portion of the conduit 92 above theorifice 93 and below the bottom edge of opening 94 serves as a dam andcooperates with orifice 93 to determine the maximlun flow rate of fuelto the pilot burner and the rate of supply of fuel to the conduit 9'! atwhich fuel will be'supplied to the main burner 'I0 as above described inconnection with 1. Liquid fuel is supplied to the main conduit 92 fromthe outlet 95 of a constant level liquid fuel supply device 98 which maybe similar to the de- 7 vice Il of Fig. l or may be any other constantlevel device such as disclosed in the patent to Russel, No. 2,317,556granted April 27, 1943, wherein safety means is included for closing theinlet valve upon occurrence of excess liquid level. The device 96 has aconstant level chamber $1 discharging through the outlet 95 which iscontrolled by a fuel metering valve 98, such for example as shown inFig. 1. The cleaning wire 99 for the orifice 83 may be attached to thevalve I as described above in connection with Pig. 4.

The liquid level in the chamber 91 is maintained substantially constantat the line R by any suitable means, such as an overflow pipe or thefloat operated inlet valve mechanism as described and shown in Fig. l.The line designated S indicates the excess liquid level at which thesafety mechanism will be actuated to close the inlet to chamber 91 andstop the supply of liquid fuel to the main conduit 92. The device 96 ispositioned relative to the main burner 'lll so that the maximum liquidlevel in chamber 91, indicated by the line S, will be below thelowermost row of air inlet ports l in the main burner lll.

The operation of the apparatus and control means of Fig. 5 is asfollows: Assuming that the safety trip means for the inlet valve tochamber vQl is in inactive position, that there is a source of liquidfuel connected to the chamber 91 so that the liquid level is standing atthe line R, that the minimum pilot fire stop Il of Fig. 1 has beeneliminated or moved so that the valve it .is closed to cut off fuel tothe pilot burner 80, and that air under pressure is being supplied tothe chamber 1I and the duct 81, then, upon opening the metering valve 98to provide the minimum flow for pilot ame, fuel will discharge from thechamber `$l through outlet 95 to conduit $2 and thence through theoriilce S3 into the pilot burner space or pan 84 where it can be ignitedby any suitable means. When it is desired'to ignite the main burner 10,the metering valve 98 will be moved toward open position to increase therate of flow through the outlet 95 in excess of that which can flowthrough the oriilce 93 and therefore the liquid head will build up inthe conduit $2 until it reaches the level of the opening or port 94 andwill thereupon ilow into the main burner space or pan 14 which has hadits bottom wall heated by the pilot burner-80 so that the liquid fuel inpan 'M will be readily vaporized to mix with the air under pressuresupplied from chamber 'I1 through ports l5. The liquid head on theorifice 93 will increase the ilow rate to the pilot burner to a desiredmaximum, thereby increasing the pilot burner flame which will ignite thecombustible mixture of air fuel in the chamber 13. It is desirable toincrease the rate of flow of fuel to the pilot burner when the mainburner is ignited in orderA to prevent the possibility of extinguishmentof -the pilot burner which may result from thev operation of the mainburner,

unless the pilot flame is increased. If the increased supply of fuel tothe pilot burner requires additional air, then the damper 89 will beadjusted to permit an increased air flow to the chamber 8B.

What is claimed and is desired to be secured by Letters Patent of theUnited States is:

l. In a heating apparatus, a pilot burner, a main burner superposed onsaid pilot burner and having a bottom wall aperture communicatingdirectly with the interior of said pilot burner, a lateral feed pipe forsupplying liquid fuel into the base of said main burner, a lateral feedpipe for supplying liquid fuel into the base of said pilot burner, anupright pipe feeding said lateral pipes and having a flow restrictingoriilce therebetween, a constant level liquid chamber having an outletdischarging into said upright pipe above said orifice, and a meteringvalve in said -outlet and determining the rate of fuel flow to saidupright pipe, the size of said orifice determining at what rate of fuelilow from said outlet, fuel will be backed up by said orifice andoverilow into said first-named lateral pipe.

2. In a heating apparatus, a pilot burner, a main burner superposed onsaid pilot burner and having a bottom wall aperture communicatingdirectly with the interior of said pilot burner, a lateral feed pipe forsupplying liquid fuel into the base of said main burner, a lateral feedpipe for supplying liquid fuel into the base of said pilot burner, anupright pipe feeding said lateral pipes and having a ilow restrictingorifice therebetween, a constant level liquid chamber having an outletdischarging into said upright pipe above said orifice, a metering valvein said outlet, and safety means operable after occurrence of excessliquid level in said pilot burner to cut oil flow of liquid fuel to saidupright pipe.

3. In a heating apparatus, a pilot burner. a main burner superposed onsaid pilot burner and having a bottom wall aperture communicatingdirectly with the interior of said pilot burner. a' lateral feed pipefor supplying liquid fuel into the base of said main burner, a lateralfeed pipe for supplying liquid fuel into the base of said pilot burner,an upright pipe feeding said lateral pipes and having a flow restrictingorice therebetween, a liquid fuel chamber having an outlet connected tosaid upright pipe above said orifice, a valve in said outlet, saidorifice being operable to restrict flow to 'said pilot burner and beingpositioned a predetermined distance below said main burner feed pipe sothat there will be a predetermined increased head of fuel on saidoriilce upon operation of said valve to supply fuel to said main burner.

4. In a heating apparatus, a pilot burner, a main burner superposed onand communicating with the pilot burner, means for supplying liquid fuelto said burners comprising a constant liquid level device having anoutlet, a main supply conduit connected to said outlet, a metering valvecontrolling said outlet and the now to said conduit, a pilot burnersupplying conduit leading from said main. supply conduit to said pilotburner, a main burner supplying conduit leading from said main supplyconduit to said main burner, Vsaid main supply conduit having a ilowrestriction orice positioned between said supo plying conduits, andmeans to cut off the supply to said supply conduit, a flow restrictingoriilce member" positioned in said supply conduit adjacent to but belowsaid main conduit and operable to restrict ow through said lowerconduit'upon opening of said metering valve to supply liquid to saidmain conduit, a valve controlling said inlet, safety means having aliquid receiving container and operable upon liquid flow into saidcontainer to close said inlet valve, and a conduit leading from saidlower conduit to said container.

6. A control device comprising a constant liquid level device having achamber with an inlet and a main outlet, a float operated valvecontrolling said inlet, said chamber having an overilow outlet, ametering valve controlling flow from said main outlet. a main supplyconduit connected to and extending downward from said main outlet, amain conduit extending laterally from said supply conduit, a lowerconduit extending laterally from said supply conduit at a point belowsaid main conduit, said main supply conduit having a flow restrictingorifice therein above the level of said lower conduit, safety trip meansIhaving a liquid receiving container and operable by weight of liquid insaid container to close said iloat operated valve, a vertical dischargeconduit discharging into said container and operable to receive liquidfrom said overflow outlet, a feed conduit connecting said lower conduitto said. discharge conduit, and a dam for said feed conduit determiningthe liquid level in said lower conduit at which liquid will flow throughsaid feed conduit into said container to actuate said trip means.

7. In a heating apparatus, a main pot type liquid fuel burner having anopening through its bottom wall and having primary air inlets throughits side wall spaced above its bottom wall, a pot type liquid fuel pilotburner extending into said main burner through said opening and havingits side wall joined in heat conducting relation to said bottom wall, aconstant level liquid fuel supply means positioned relative to said mainburner such that the maximum pos- 10 sible liquid level in said supplymeans will be below said primary air inlets, said fuel supply meanshaving an outlet, means to control the rate of flow from said outlet, amain fuel conduit leading from said outlet and discharging into saidmain burner, a fuel conduit leading from said outlet and discharginginto said pilot burner, a restricted orifice means in said lastnamedconduitfand operable to restrict fuel flow from said outlet to saidpilot burner, and a dam interposed between said orifice means and saidmain conduit and cooperable with vsaid orifice means and blocking flowto said main conduit to determine the substantially maximum rate of fuelflow to said pilot burner, said dam and said orice means cooperatingwith said outlet control means to determine at what minimum rate of flowfrom said outlet fuel will be fed to said main burner.

WALTER S. LANDON.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 425,667 Fenby Apr. 15, 18901,109,768 Laux Sept. 8, 1914 1,377,994 Wagner May 10, 1921 1,556,817Higgins Oct. 13, 1925 1,650,065 Dial Nov. 22, 1927 1,891,855 White et alDec. 20, 1932 1,987,179 Chadwick Jan. 8, 1935 2,075,242 Todaro Mar. 30,1937 2,086,884 Sherman July 13, 1937 2,247,689 Kirkpatrick July 1, 19412,253,056 Ullstrand Aug. 19, 1941 2,346,817 Breese et al Apr. 18, 19442,353,341 Klonaris July 11, 1944

